1. Field of the Invention
The present invention relates to a piezoelectric module, and more specifically to a piezoelectric module including a piezoelectric resonator and another circuit element.
2. Description of the Related Art
Various types of filters using a piezoelectric resonator are known. In a piezoelectric module such as a filter including a piezoelectric resonator, the piezoelectric resonator and another circuit element may be integrally configured. Examples of the above another circuit element include an inductor, a capacitor, or the like configuring a matching circuit for the piezoelectric resonator.
Japanese Unexamined Patent Application Publication No. 2010-93398 describes a filter in which a piezoelectric resonator and a capacitor are formed on a surface of a substrate. However, in the configuration of the filter described in Japanese Unexamined Patent Application Publication No. 2010-93398, a circuit element is formed on the surface of the substrate, thus the circuit element has low weather resistance, and it is necessary to further add a structure which improves the weather resistance.